Nailing machine



Dec. 29, 1942.

J. vA. loHANssoN NAILING MACHINE Filed June 25. v1940` 4 Sheets-Sheet l 1N VENTOR Jol-IAN H. L/oHA NSSON By ATTORNEY Dec. 29, 1942. J. A. JQHANs-so'N NAILING MACHINE l 4 Sheets-Sheet 2 Filed June 25, 1940 /N VENTOR N 9M M Mm @U14 A N A. L, J

Dec. 29, 1942. J. A. JoHANssoN NAILING .MACHINE 4 Sheets-Sheet 4 Filed June 25, 1940 [NI/ENTOR JOHAN A L/o HANssoN BY I " "5 ,4 TToR/VEY A Patented Dec. 29, 1942 UNITED l AS''ATES PATENT OFFICEA v 2,306,627 a Y NAILING MACHINE Johan A. Johansson, Berkeley, Calif.

Application .time 25, 194,0, seriai'No. 342,295

7 Claims.

The invention relates to a nailing implement for continuous operation for nailing a succession of floor boards, or similar elements, in place.

A general object of the invention is to provide an improved nailing unit having a nail hopper and 4 provided with a motor which effects the operative disposal and release of a swinging hammer and the positioning of a nail from the hopper for its driving by the released hammer. l

Amore specific object is to provide an improved Ahammer-aetuating means for a nailing unit of the character described.

Another object is to :provide an improved and .particularly simple nailing head having a single nail-driving element which is readily dismountable merely by lifting it from its operative place.

Another object is to vprovide Aa particularly simple and effective device for automatically in suring the supply of solely one nail at a time to the head. Y Y

A further object is to provide an improved means for mounting thenails in alignment in a slideway which conveys them to the head.

The invention possesses other objects and features of advantage, some of which, with the foregoing, will be set forth or beapparent in the following description of a typical embodiment of my invention, and in theaccompanying drawings, in which, Y y

Figure 1 is a side View of a nail-driving implement embodying my hammer thereof in raised position.

Figure 2 is a plan view of the implement with part broken away on the line 2-2 in Figure 1. v v

Figure 3 is a sectional elevation at the line 3-3 in Figure 2, and shows the relation of the parts when the hammer is resting upon a nail-driving plunger of the unit.

Figure 4 is an enlarged sectionalelevationY on the broken line 4-4 in Figure l.V Y

Figure 5 isan enlargedand fragmentary section taken at the line55 in Figure 1.

Figure 6 is an enlargement. `and fragmentary section taken at the broken line 6-6 in Figurel.

Figure '7 is a vertical section through the head of the hammer.

Figure 8 is a perspective View` of an impact member used in the hammer-head.

Figure 9 is a sectional ew of hopper of the unit, line 9-9 in Figure 1.

Figure l0 is a side View of the hopper, the side cover thereof being removed, and parts of the structure being broken away.

invention and having the a nan-.feeding the view being taken at the .Y Figure 1l is as'ection of the yhopper taken at the lille iii Figlllello. l

Figure l2 is a fragmentary section of the' toolr head, and -is taken at the line |'2-I2'in Figure 2. Figure 13 is a stepped 'section at |3--I3v in Figure 12.

contact Figure 14 is a perspective view of certain nailreleasing elements ofthe head.

As particularly shown, the features of my inventionareV incorporated inthe structure of a nailing unit having a swinging hammer I6 operative against a nail-driving plunger I1 mounted in a nailing head I8 to which nails N are automatically supplied from a hopper I9. The. aforesaid elements are carried ony aunitary frame whichalso mounts an electric motor 2|. which vfis' operativelyconnected to the hammerl land hopper for effecting the operationsof the latter elements.4 Y

The relatively long and narrow frame for the present embodiment of my invention comprises a generally triangular plate member 22 which directly supports the motor 2| intermediately thereon and carries the head I8 at its forward point. Side frame members 23 extend rearward- .ly Vfrom the rear corners connections withV a cross-member 24, whereby ythe'mernbers 22 and 23 and 24 jointlyprovide a vbase portion of themember 22 to of the frame.' A pair of `Support feet 25 is provided at `the member 24, and a single support foot 26 Ais provided at the forward portion of the'member 22, 'whereby said feet jointly provide the plane of support for the unit. Since'the present unit is to be moved over placed boards to be nailed down, the feetj25 and 2B are kpreferably provided with anti-friction embers to engage theboards; as shown, the elements of the feet comprise ballcasters For a reasonto be hereinafter broughtout, the forward frame portion is preferably sup- J ported'on a compression spring` 26 which is operative between the foot,26 and the plate 22 to resiliently support thefrontlportion of the unit.

`Spaced,framelposts 28 extend upwardly from the rear end of the frame andare connected at their tops by a cross-member 29, and spacedposts 3 I extend upwardly from the forward'ends of the sidefframe members 23 and are connectedat their tops by a cross-member 32. VA longitudinal sidemember 33 connects the upper'end of each post 3| with the corresponding post 28. For providing a frame having the desirable qualities of lightness and strength, certain. of the 4frame members may be of angle section, as shown. In

the ypresent instance, the members 22 and 3| and 32 vand 33 are provided as integral parts of a single casting, rather than the elements of a f built-up structure.

A shield plate 34 substantially closes the rearward face of the frame portion provided by the members and 23 and 29, and a control switch 35 for the motor 2l may be mounted on the plate. A bracket arm 35 is mounted at the rear of the frame and provides an upright handle 31 for use in moving the implement about. The power wires 38 to the switch 35 are shown as extending axially through the handle 36, and the wires 39 from the switch to the motor extend longitudinally through the frame in any path which is clear of moving parts.

The rear upper cross-member 23 of the frame mounts mutually parallel wrist pins 4l and 42 between spaced pairs of ears of the member, said wrist pins rotatively carrying gears 43 and 44 which are arranged for a constant mutual meshing thereof. The gear d3 is fixed at the rear end of the handle 45 of the hammer I5, and the gear '54 is fixed at one end ofV a depending arm 46 which has its other end connected by a relatively strong tension spring 41 with an anchor- Aage member 48 fixed on the bottom frame member 22. The arrangement is such that an upward swinging of the hammer about its pivotal axis at the pin 4l to position its head 49 for a working blow against the nail-driving plunger l1 is yielding resisted by the tension spring 41 which stores up energy for swinging the hammer in a working stroke against the plunger when it is released.

Means are preferably provided to adjustably resistance of the spring 41 may be adjustably Varied to meet variable operating requirements for the hammer, due, for instance, to diierences 'in the hardness and/or thickness of the boards to be nailed.

It will now 'be noted that va shaft 53 is journalled in and between the upper side frame members S3 and carries a cam member 54 having a pair of like and oppositely directedI arms extending from 'a hub 55 whichis rotatable by and with the shaft 53. The arms 55 are arranged for rotation in a common plane parallel to the plane of swinging of 'the hammer handle 45, have their forward edges 51 curved rearwardly and spirally lto their free extremities, and have their rearward edges 58 convexedly curved. As the hub 56 isrotated, the edges 51 of the cam arms Y55 are successively operative against a roller 59 mounted on'the hammer handle 45 to swing the hammerupwardly against the resistance of the spring 'Q1 until the arm extremities are reached and the hammer is released for working strkes under the influence of the spring. An end of the cam shaft 53 which extends from one side of the frame carries a gear 62 which constantly meshes'witha gear 63 carried on the power 'output shaft of 'the `motor 2l whereby the cam '54 may actuate thehammer I6 in the described manner.

A'As shown, the hammer handle 55 is longituplane of operation of 'the cam arms, for freely receiving said larms in the slot between the fork sides 60. The extremities of the fork sides 60 have the gear 43 fixed to and between them, and a shaft 6| xed to and between the fork sides 66 rotatably carries the roller 59 against which the cam edge faces 51 are operative for raising the hammer into striking position. This arrangement is understood to provide for the operation of the cam 54 in the central plane of swinging of the hammer handle and so minimize friction in the operation of the hammer. The roller 59 is preferably so positioned on the handle 45 that it lies directly above the shaft 53 when the hammer is fully lowered Aas in Figure 3.

A clutch means is provided for rendering the cam 54 inoperative while the motor 2l is operating. As particularly brought out in Figures 5 and 6, the shaft 53 is divided at a point thereof between the cam hub 56 and the supporting frame member 33 nearest the gear 62 to provide abutting sections 64 and 65 which respectively have the `cam and -gear ixed -to them, the clutch means being cooperative qbetween said shaft sections. The shaft sections 64 and 65 are stepped together at their-mutually abutting ends, whereby the shaft bearings in the upper side frame members 33 may fully-journal the shaft. Axial separation of the shaft sections is prevented by a thrust plate 66 mounted on the frame members 33 which provides the bearing nfor the cam Ysection '64, and a radial shoulder 61 provided on the shaft section 65 iin-close opposition to the inner end of the bearing sleeve for the section.

A Lpin 68 is `non-'rotatably -slidable-in a -complementary bore extending-axially through the camhub 56 and has-'one end-normally engaged in asegmental fsocket 69 provided in the opposed end :portion -of the shaft-section 65 Vwhich has lapproximately thef-same diameter as the opposed hub end. A compression spring 1I is'operative between the fother lend of the `.pin 268 :and Athe plate V66 -for constantly :urging a disposal land retention Aof the pin lin the socket .63 as ra releasable clutch means 'providing `for a driving of 'the'cam 454 by the motor. eAn annular groove 12 of uriiform-cross-sectionis #provided in the hub-56 of `the cam 54 to vextend into the bore vided with a notch 13 in its outer side, said 4notch having `a-nifajorportion thereof 'in advance lsection 55 and so 'fstopla irritation of v'the .cam

and the actuation of the hammer |6 Jwhile the shaft portion -65 rotates. Y'As is brought 'out in Figures l and lar-idfl-and-G, the .member 14 comprises the free -ri'cl l'o anl arm '151 having its other end 'providedwith-anleye`16 which receives -a pivot-'pin 511 lfi'xed `to and between the lower ideframe 'nrem'be'rsf '-Theimember 114 .Lis .provided ywith an `arcuate i notch Aat its 4groove-engaging edge, and its groove-engaging portion 18 at said notch vlis taper-cdas a Wedge longitudinally thereof Vin l-such f manner that the working rotation Yof 4the hub is toward fthe wedge lbase to provide for the functioning -.of the Awedge against the inner side ofthe pin notch13 to withdraw the pin-'66v and Isovdisconnect the cam for its stopping when fthe member 1.4 :has :been swung to dispose li-ts 'iwe'dge portion :18 in the hub groove; this release of the cam is arranged to occur when the hammer is in the lowered position shown for it in Figure 3.

Means areV provided for swinging the arm 15 to operatively engage the wedge 18 in the hub groove 12 for withdrawing the clutch pin `68 against the resistance of the spring 1I. As shown, a pull rod 19 extends forwardly from the arm 15' which disposes the member 14 at the rear side o'f the hub for swinging the arm forwardly against the resistance of a spring 8| which extends from the arm to an anchorage on the adjacent upper side from member 33. At its forward end, the link 19 is connected to one arm of a lever 82 pivoted on a bracket member 83 for rocking about an upright axis, said bracket being mounted on a forward upright frame post 3l near its top; as shown, the pin-displacing device is disposed to the right of the plane of operation of the arm lifting cam 54.

By particular reference to Figure 6, it will be seen that the bracket 83 provides a tubular and forwardly directed handle 84 through which a push rod 85 slidably extends to a connection at its rear end with the other end of the lever 82. The forward handle 84 is' arranged for `use cooperatively with the rear handle 31 for manipulating the tool over the Work, and the present clutch control device is so arranged that a mechanic may, Vwhile grasping the handle 84, press in on the push rod 85 to displace the member 14 for causing a cessation of the hammers actuation which normally occurs whenever the motor is operating.

Should it be desired to stop the hammer from actuating `while the motor is operating and without requiring the continued pressure of the rnechanics hand on the rod 85, a pin 8E, or other A Ypinlike member such as a nail, may be engaged through and between holes 81 and 88 respectively provided through the handle and thrust rod 85, said holes registering only when the rod 85 is pushed in to disengage the clutch pin 68.

It will now be noted that the nailing head assembly i8 includes an elongated block `81 provided with a uniform longitudinal bore 88 in which the plunger YI1 is closely and slidably engaged. The block 81 is suitably fixed to the forward end of the frame member 22 withthe plunger I1 to it; as shown, a lateral block extension k89 is bolted to the front end of the member Z2 to dispose the plunger inr perpendicular relation to the bottom plane of the frame and in the line of operation of the hammer I6. At its upper L end, the plunger i1 is provided with ay striking head portion 9! which is larger than the plunger body, and a compression spring 92 encircling the plunger is constantly operative between the head 9i and a seat ring 89 which freely encircles the plunger above the upper block end to urge the disposal of the plunger to the raised position thereof shown in Figure 1,

At its lower end, the bore- 88 slidably receives the upper and smaller portion of a cylindrical nose-piece 93 having its exterior stepped to provide a shoulder which may engage the lower end of the block B1 to limit the extension oi nose-piece into the bore 88. The element 93 provides a guide for av nail to be driven, and is provided with an axial bore 94 which is jus, large enough to permit the free passage of a nail N therethrough, said nail having a head which extends beyond the cylinder of its shank. To facilitate the entry and centering of a nail operative in fixed angular relation i therein, the upper end of the bore 94 is conically enlarged or counterbored. The normal spacing of the lower end oi the head block 81 from the base plane of the unit under the supporting iniiuence of the foot spring 28 is preferably such that the nose-piece 93 gravitally rests on the board to be nailed down without bearing the front-end weight of the unit and with its shoulder relatively close to the lower block end; in this manner, a nail being driven is constantly enclosed at the floor line against its lateral bending thereat, while the nose-piece limits any downward movement of the nailing head.

A drive pin e5 is mounted in the lower end of the plunger i1 in the common axial line of the bores 38 and 94 of the block and nose-piece respectively. The pin 95 is arranged to enter the bore behind a nail thereinr for driving the nail through and beyond the latter bore to set (countersink) its head in the floor to a degree determined by the working stroke oi" the plungerl as limited jointly by the striking of the top of the nose-piece by the lower plunger end and by the extension oi the pin .beyond the lower plunger end. Preferably, and as shown, the pin'e is threadedly engaged in the plunger to provide for adjusting its effective length to determine the set oi a driven nail. When the plunger is. in raised position, suiiicient space is left below and about the drive pin 95 to permit the introduction of a nail laterally into the bore 88 for its gravity fall into the bore 95% of the nose-piece 93 to have its point rest on the under lying floor board for its subsequent driving thereinto.

Means are provided whereby the force o the plunger-raising spring 93 is exerted solely between spaced points of the plunger when the plunger is in its fully raised position, with the purpose of permitting a free lifting oi the plunger out of the head bore to be retained solely by gravity. As particularly shown, the plunger is provided with a longif tion to the bore 88 and of a depth slightly ceeding the length of the member.

tudinal slot 9E extending upwardly from a point of the plunger shank which is below the top of the vhead block 8'? when the plunger is raised, the slot 96 being of uniform' cross-section. The slot 96 constantly and freely receives a pin 91 comprising a lateral extension of a member 98 which is restrained to movement solely axially of and with respect to the plunger. When the plunger is fully raised, the spring 92 is operative to dispose the seat-ring 98 at a limiting distance from the plunger head as determined by the engagement of thepin 91 with the bottoni end of the slot, the spring force then being entirely coactive, through the ring St and the member 98, between the relatively ,fixed plunger parts comprising the head 9i and the stop provided by the bottom end 99 of the slot 98.

As particularly illustrated, the member 93 is cylindrical and is slidable in a complementary guide socket I8! extending into the head block 81 from the upper end thereof in parallel relaexsie, connects the socket and bore in mutually dial relation thereto for the extension oi the pin 91 therethrough to permita disposal or the member 98 entirely below the block iop to pron vide for the engagement of the seat-ring 9?! against the upper block end to support the raised plunger upon the spring S2. This arrangement permits a working depression oi the plunger i1 through the seated ring against the full re- 88 in which it is arranged f sistance of the spring 92, it being understood` that the resistance of said spring is preferably but little more than is required to insure the full raising of the plunger above the washer 90 after a working stroke thereof, and that the length of the plunger slot is such as to permit a full working stroke of the plunger without con- `tact of its upper end with the pin 91. As shown,

the slot |02 extends outwardly of the socket lei to slidably receive an extension |93 of the member 98 which, with `the pin 91, cooperates with the slot sides to prevent a rotation of the member to avoid any engagement of the pin ii'i with the sides of the plunger slot 95 and so prevent any frictional wear of the pin or slot sides as the' movement of the plunger is checked and cushioned by the reaction of the spring 92 against the ring to bring the plunger to rest. If the inertia of the plunger should be sufficient to lift the ring from its seat in the head block during the stopping of the upward plunger motion, the. assembly will subsequently fall by gravity to reseat the ring on the head block as the support for the plunger assembly.

The shock and noise of impact during a working stroke of the hammer are minimized by providing the hammer head 49 with a non-resonant and slightly yielding striking face |05. As shown, the head 49 is generally tubular and provides cylindric bore portions |06 and |01 above and below an intermediate cross partition |08 having a cen-i tral opening |09 therein. An impact member is frictionally engaged in the lower bore |01 to provide the working face for engaging the plunger head 9|, said member preferably comprising a cylindrical roll of rawhide or some other mai terial which is relatively non-resonant and nonresilient. A disc |I2 is preferably installed between the inner end of the member ||I and the partition I 08 whereby removal of the member for its replacement may be readily effected iby opi eratively applying a suitable punch (not shown) against the disc through the opening |09 of the partition |08. The head space or bore above the partition |08 is arranged to receive an appropriate weight; as shown, a weight member |I3 is threadedly mounted in the bore |06, it being understood that the weight provided in said bore may be large or small to satisfy different operating conditions for the nailing machine.

Referring particularly to Figures 12 and 14, it will be noted that a hole or bore ||4 extends obli quely upwardly in the head block 81 from the top of the nose-piece 93 within the plunger-receiving bore 86 to an opening at the rear exterior of the block for the gravity and point-down delivery of a nail N into the nose-piece bore 94 from a chute or slide-way assembly I I5 from which nails are varranged to be automatically supplied within the head one at a time and just before each plunger operation. A horizontal guideway is provided across the upper end of the hole I|4 and reciprocally carries a nail-releasing plate member I I 6 which is normally disposed to hold back a line of nails in the slideway ||5 and is longitudinally displaceable to release but one nail at each nail- "releasingdisplacement thereof. As shown, the

guideway for the member I I6 is cooperatively provided by and between the head block and a member I|1 fixed thereto and providing spaced ears I8 on which the lower end of the slideway II5 is mounted.

Y The slideway II5 essentially comprises opposed vertical plates ||9 mutually spaced to freely receive the nail shanks between them While the nail heads rest on and span their upper edges` which denne a slot |20 inclined for gravity movement of the nails therealong and toward the nailing head. The slideway thus provided is arranged to normally support the line of nails with the upper end portion of the forward nail N against the outer and rearward face of the member I I6 while the nail shank depends in the upper end of the hole I I4. The member I I6 is `notched from below to provide a nail-escape opening I2I at a point to one side of its area which normally bars a delivery of nails from the supply slideway, and means are provided for insuring the escape of but one nail at a time when the member I IE is shifted to dispose the opening |2| in alignment with the line of nails. As shown, a sharpened separating arm |22 on the member extends across the opening from its side opposite said nail-retaining area, and is so spaced from the member that its point may engage between the leading and second nails of the line as the member is shifted whereby to permit the escape of the leading nail through the notch I2 I and hold back the rest of the nails. When the member I |6 makes a return stroke, the new leading nail is released from behind the arm |22 to move against the member I|6 in preparation for a repetition of the described nail-feeding process.

Means are provided for actuating the nail-releasing member I6 in synchronism with the operation of the hammer. As particularly shown, a rock shaft |23 is journalled in the frame longitudinally thereof, and below the level of the member ||6, and carries upwardly extending radial arms |24 and |25 at its forward and rear ends respectively. The arm |24 comprises a plate having a longitudinal slot |26 therein which slidably and constantly receives a pin |21 extending xedly from the member I I6 whereby to provide in effect, a universal joint between the arm and member. A bell-crank lever |28 is pivoted to the top of the upper frame portion at a forward point thereof and to one side of the plane of operation of the cam 54, said lever having an arm I 29 providing a contact lip or edge |3I normally disposed in the path of movement of the working cam edges 51 by the appropriate action of a tension spring |32 on the lever.

The other arm |33 of the lever |28 is vertically slotted to freely receive the free end of the arm |26 of the rock shaft |23, and extends in such a relation to the arm I 29 that the shaft arm |25 may engage the inner side of the adiacent member 33 as a stop means for the arm when the member I I6 is disposed to hold back the nails at the head I8. As shown, the spring |32 is operative between the free end of the arm I 29 and an anchorage in an upper side from member 33 whereby it yieldingly holds both the member IIE and the contact lip I3| in their normal positions. The arrangement is such that just before one cam arm is disposed to release the raised hammer for a working stroke, the other cam arm wedgedly engages the lip |3I and deflects the lever |28 to rock the shaft |23 to move the member ||6 to release a nail for its arrival in the nose-piece 93 just before and substantially simultaneously with the striking of the nail-driving plunger I1 by the hammer head.

As shown, the chute or slideway I I5 slopes downwardly to the nailing head from within the chamber of the supply hopper |9 which is mounted on the frame to one side of the zone of operation of the hammer, and includes a means for automatically providing and maintaining a line of nails in the slideway, the various details of the'hopper and said means being disclosed in Figures 9 to 11 inclusive. At the upper end of the slideway within the hopper the side members I I9 thereof have extensions directed upwardly and away `from each other to provide the sides of a sloping trough |35 having its bottom comprising a continuation of 'the slot |20 to receive only the nail Shanks as the rest of the slideway. Y

If nails are deposited at random in the trough |35, the points and Shanks of some will fall into the trough slot |20 and so effect a positioning and support of such nails for their movement along the slideway to supply the nailing head. The remaining nails will slide downwardly in the trough to the lower trough end to fall into the underlying bottom of the hopper casing |31 from which they may be automatically redeposited in the trough through the operation of a rotary conveyor device which is provided for operation within the casing. It will be noted thatthe slideway is perpendicular to the head member ||6 at its discharge end and may be straight or be laterally bent out of a straight line between the hopper and head as may be required to make the connectionbetween the hopper and the head.

The casing and a shaft |38 is journalled axially therein to extend through and from a xed casing end |39. A gear |4| is provided on the extending end of the shaft- I38, and the casing is so supported on the machines frame by brackets |42 and |43 that the gear |4|- constantly meshes with the gear 62 on the cam-operating shaft 53 for the actuation of the first shaft while the motor 2| is operating. A removable disc |44 having a peripheral flange |45- provides a closure for the other casi-ng end, and is provided with a socket bearing |46 for receiving and centering the opeposed end` of the shaft- |38 while its flange |45 fittedly receives the casing end. For a reason whichvwill hereinafter become apparent, the bore of the casing tapers from a cylindric central portion thereof toward both its ends. Also, the end of they slideway |-|-5- including the trough is above and oblique to the shaft |38- and extends through acasing opening |41 whichis nearer the fixed casing end |39 than the slideway extremity in the casing.

A hub- |48 ismounted on the shaft |38 adjacent the bea-ring |46 and carries-a radial arm |49 provided with a, terminal bladel |5-I extending axially of the sha-ft to a point centrally of the casing, and having its plane parallel to and generally radial: of the'v sha-ft axis. The blade |5| is arranged for movement in the direction indicated in Figure 1'0- for pushing nails from the casing bottom around the opposed casing bore to apoint at the top of the casing from which they may drop into the trough |35- for the mounted disposal of some ofthem inthe slideway, it being noted that the outline and previously described obliqueposition of the trough are designed to permit this.v The action is arranged to berapid enough tocentrifugallt7 holdthe nails tothe overhang-ing bore portion substantially until the top thereof is'reached by the-nails.

|31 is of generally cylindric outline As particularly disclosed, the arm hub |46 yis free on the shaft |38 and is provided with axially directed clutch pins |52 which are normally disposed in the path of movement of complementary clutch pins |53 extending from the end face |54 of a sleeve member |55 fixed on the shaft |38. A compression spring |56 encircles the shaft and is yieldingly operative between an annular flange |51 at the shaft extremity and a seat provided by and within the hub |48 to constantly urge a disposal of the ends of the pins |52` against the end face |54 of the member |55. The mutually engageable sides of the pins |52 and |53 are co-mplementarily bovelled whereby a holding ofthe blade it?! against rotation,A as by jambing of nails between it and the casing bore, may automatically provide for a disengagement of the pins |52 the shaft pins |53 by shifting the hub axially, said pins otherwise-providing a clutch connection between the shaft |38 and the arm |43 of the conveyor blade |5I; the operative arrangement is understood to constitute an overload release. l

Nails may be supplied to the hopper I9 through va feed chute assembly |58 mounted on the hopper casing |31 and arranged to deliver nails therefrom through a horizontal slot |59 provided through the casing side at the bottom of the chute.- The delivery of the nails to the hopper from the chute |58 isA preferably at a controlledrate whichV approximates the average rate at which nai-ls are to be driven by the present unit, and the described device for mounting nails from the hopper orithe slideway ||5 operatesat a faster rate so that the slideway may generally be ful-ly loaded tol supply the nailing head I8'. l

"As shown; the chute |58 comprises side walls |6| and IGZ- extending upwardly from a bottom |63 whichv slopes to a point of the casing at the bottom lineof the slot |59 `and is somewhat wider than said slot.V The chute side wall |6I is fixed flat against the casing` end wall |39 and the lower ends of the chute side Wall |52 and bottom |53 are 4fixed directly to the side casing wall where they abut it; the chute thus vextends rigidly from the casing, it YKbeing noted that the hopper'support bracket |43 is operative between the machine frame and the upper chute end which is closedV with a sloping wall.

A- partition member |64 is mounted in and across-the chutef |-58 for adjustment in its plane, which plane slopes rearwardly frornvthe vertical to define an acute angle with the bottom plane of the chute,` The straightbottom edge of the partition |64 is- `arranged: to be varia'bly spaced from the chute bottom to ad-justably vary the rateof escape ofnai-ls beneath itfrom the chute spa-cer at itsupper side; As shown, the partition |64 com-prises; aplate member |65 havinglike tri-angular side -anges |66 and atop flange |61 extending transversely from its lower (rear) side, all of said member-'s o f the partition being mutually connected at their abutting edges.-

Thesideflanges |66 are provided kwith rectangular slots |68 immediately adjacent the plane of the lower face of the partition plate |65, said slots receivingk therethrough a at -strapelike member |69 which has its ends secured to and betweenthe chute sides |62. The slots |68 are longer than the widthofthe members |69 thereat topermita guided shifting of the partition |6|l` in its plane, the bottomedge of said partitionl being spaced from the chute bottom and the partition being-frictiona-lly held in its adjusted posiion.- s

A vfalse bottom member |1| is provided in the chute |58 and extends in its upper portion to a point spaced from the upper sides of the partition |64. The space |12 between the bottom members |53 and |1| receives the upper end of a plate member |13 which extends into the cavity of the casing |31 through the bottom portion of the slot |59 and is arranged for reciprocation in its plane by reason of the rotation of the shaft |38, it being noted that the plate |13 is guided for its movement in the plane of the space |12 by reason of its sliding engagement between the chute bottom members |63 and |1|.

A flange or ear |14 extends transversely upwardly from the slide plate |13 at its inner end portion and is connected with the shaft |38 in a manner to provide for thel reciprocation of the slide plate in its plane as the shaft rotates. As shown, an eccentric disc |15 is mounted on said shaft adjacent the plane of the flange |14 and engages in a complementary bore provided in one end of a member |16 having its other end pivoted to the flange |14 at a pivot pin |11, whereby a rotation of thel shaft is arranged to effect a reciprocation of the plate |13. The portion of the slide plate |13 which is movable through the slot |59 is preferably roughened at its upper face, as by projection |18 on the plate.

By particular reference to Figure 10, it will be noted that nails N deposited in the chute portion above the partition |64 will, by reason of the natural vibration of the machine and the action of the plate |13 and its projections |18, assure a more or less orderly arrangement in the angular corner provided by the partition and the chute bottom in general parallelism with the bottom edge of the partition, and will be progressively freed to escape beneath said partition edge for travel down the plate |13 and through the opening |59 to thereafter fall from the plate into the underlying sloping portion of the casing for their final disposal in the zone of action of the conveyor blade It will be understood that the partition |64 is to be so adjusted that the rate at which nails are freed to escape beneath it is no less than the average rate of application of the nails by the implement, and has a distinct relation to the speed of operation of the conveyor blade. Also, the partition |64 and plate 13 are cooperative as a gate means for controlling the rate of discharge from the chute into the hopper.

From the foregoing description taken in connection with the accompanying drawings, the advantages of the construction and operation of the present nailing machine will be readily understood by those skilled in the art to which this invention appertains. While I have described the features and principles of operation of a structure which I now consider to comprise a preferred embodiment of my invention, I desire to have it understood that the showing is primarily illustrative, and that such changes may be made, when desired, as fall within the scope of the following claims.

I claim:

l. In an implement for movement on and over a succession of placed boards and the like to nail the same in place, an elongated frame of rigid structure, a head block xedly mounted at the forward frame end and having a bore extending therethrough in fixed angular relation to the frame base, a nose member provided with a nailreceiving bore longitudinally therethrough and slidably engaged in said head block bore, and

extending Vbelow the block 'for its supprt nthef underlying board, a step means on 4said memberA for limiting its extension into the block, a naildriving plunger operative in the bore of the nose member, a single sliding support foot for the for-H ward frame` end, means resiliently supporting then forward frame end upon said forward support foot to normally dispose the head block above' the g stop means on the nose member,and a pair of thereover, a head block'xedly mounted on the frame and having a bore extended therethrough in transverse relation to the support plane ofthe frame, a normally raised and depressible plunger for actuation against a vnail disposed therebelow in the head block togdrive the nail through an underlying board, a swinging hammer having its handle pivotally mounted on the frame and arranged for the action of its head against the head end of said plunger to drive the nail therewith, a spring means constantly and yieldingly operative to resist a swinging of the hammer' to a pre-determined position from which a working stroke of the hammer against the plunger is to be taken, a gear and lever connection between the hammer handle and the spring, means adjustable to adjust the effective spring resistance,-

a cam means directly operative against the hammer handle in the plane of action thereof to dis-- pose the hammer in said limiting position and thereupon release it for a working stroke, and means to actuate said cam means.

3. In a nailing implement, a nail-driving plunger, a hammer movable independently of thek plunger for striking actuation against said plunger, a spring means operative to effect a working stroke of the hammer, a rotary cam operative to successively dispose the hammer for a working stroke thereof and release the hammer for the working stroke, a drive shaft forl said cam, a power drive for said shaft, and a releasable clutch connection between the cam and shaft. Y

4. In a travelling nailing implement, a rigid frame for moving support on the Work, front and rear handles on the frame for use in manipulatfing the implement over the work, a nail-driving hammer, a spring means constantly and yield` ingly operative to resist a disposal of the hammer in a predetermined position from which a `working stroke of the hammer is to be effected, a

control means for the hammer repetitively operative to dispose the hammer in said position and thereupon release it for its Working strokes under the influence of the spring, a power drive for said control means, a normally engaged releasable clutch connection between the control means and the power drive, and means operable by an` operators hand grasping the forward said handle for guiding the implement to release said clutch.

5. In a nailing unit of the type described, a`

head block having an upright guide bore extending therethrough, a normally raisednail-drivingY plunger slidably engaged in said bore for its depression to drive a nail disposed below it inthe bore, a hammer for actuation toV effect a naildriving depression of the plunger, a Ynail-inlet passage extending downwardly from a point on a block side to the bottom portion of the guideV bore for delivering a nail in upright position beneath the raised plunger in the latter bore. a.-

slideway providing a line of uprightly disposed nails terminating at'the inlet end of the nailinlet passage, a member'operative as a gate while the'plunger is raised to admit the leading nail from the line to the nail inlet passage while holding back the remaining nails, and a cam means directly operative to alternately actuate the hammer and gate member.

6. In a travelling nailing machine, a rigid frame, a head block xedly mounted on the frame and having an upright bore extended therethrough, a normally raised plunger for actuation against a nail disposed therebelow in the head block to drive the nail, a swinging hammer having its handle pivotally mounted on Athe frame andrv arranged for the action of its head against thev head of said plunger to drive the nail therewith, a spring means constantly and yieldingly operative toresist a swinging of the hammer to a predetermined position from which a working stroke of the hammer against they plunger is to be taken, a gearand lever connection between the hammer handle and spring, means directly operative against the hammer handle to dispose the hamand depressiloleV CJI mer in said limiting position and thereupon release it for a working stroke under .the influence of theV spring, and means to actuate said last means. y

7. In atravelling nailing machine, a frame, a head'block xedly mounted on the frame and having an upright bore extended therethrough, a normally raised and depressible plunger for actuation against a nail disposed therebelow in the head block to drive the nail, a swinging hammer having'its handle pvotally mounted on the frame and arranged for'the action of its head against the head'end of said plunger to drive the nail therewith, a spring means constantly and yieldingly operative to resist a swinging of the 'hammer to-a predetermined position from which a working stroke of the hammer is to be taken, means adjustable to adjust the effective spring resistance, i and means for actuation againstl the hammer handle to dispose the hammerV in said limiting position and thereupon release it for a working stroke under the influence of the spring. Y

JOHAN A. JOHANSSON. 

